Flow meter for measuring small quantities of liquid fuel

ABSTRACT

A flow meter for measuring small quantities particularly of liquid fuels. A chamber is provided with cups mounted to rotate in a paddle wheel manner by the flow of liquid. Magnets of opposite polarity are carried by each cup. An electromagnet magnet alternately attracts and repels the cups to bring then into filling and them emptying position. A reed switch is actuated by the magnets to provide a measure of flow and reverse the polarity of the electromagnet.

[ 1 June 12, 1973 United States Patent 1 Maeshiba [54] FLOW METER FORMEASURING SMALL 2,998,722 9/1961 Jaquith 73/219 QUANTlTIES 0 LIQUID FUEL3,093,973 6/1963 Williams.t.........,... 73/229 [76] Inventor: SozaburoMaeshiba, 33-32 4-chome Primary Examiner Herbert Goldstein HakataekmaeFukuoka Japan Atzomey-Holcombe, Wetherill & Brisebois July 2, 1971ABSTRACT 22 Filed:

21 App]. No.: 159,300

A flow meter for measuring small quantities particularly of liquidfuels. A chamber is provided with cups mounted to rotate in a paddlewheel manner by the flow of liquid. Magnets of opposite polarity arecarried by each cup. Ari electromagnet magnet alternately attracts andrepels the cups to bring then into filling and HM 2H2 3 100 "0 2 WW m2"0 "Q U a .c Ur 1e S I. o C m xw UIF ii] 2 8 555 .llrL

them emptying position. A reed switch is actuated by [56] ReferencesCited the magnets to provide a measure of flow and reverse UNI ST N Sthe polarity of the electromagnet.

3,599,607 8/1971 Wallicit............................ 73/217 X 1 Claim,5 Drawing Figures PATENTEUJUN 12 I975 SHEEI 1 OF 2 1 FLOW METER FORMEASURING SMALL QUANTITIES OF LIQUID FUEL SUMMARY THE INVENTION suringthe consumption of oil used for central heating,

etc., and are especially unsuitable for measuring small quantities from0.1 L to 4 L per hour. My meter is, however, capable of measuring suchquantities quite accurately and is therefore quite suitable for use inthe central heating field.

These and other advantages of this invention will be better understoodupon consideration of the following detailed description of a preferredembodiment of the invention with reference to the accompanying drawings,in which:

FIG. 1 is a front view of a flow meter for measuring extremely smallquantities according to this invention, with part of'the casing brokenaway',

FIG. 2 is a vertical section taken along the line 11-11 of FIG. 1;

FIG. 3 is a sectional view taken along the'line III-III of FIG. 1;

FIG. 4 is a diagram showing the principal part of the flow meter formeasuring extremely small quantities according to this invention; and

FIG. 5 is a diagram showing the connections when this flow meter formeasuring extremely small quantities is used.

Referring now to FIGS. 1-5, the illustrated embodiment of the flow meteraccording to this invention will now be described.

As shown in the drawings, an oil pipe C connects a liquid fuel tank A toa burner B. The pipe C is interrupted intermediate the tank and burnerby a casing 1. A plural of cup-shaped vanes 3, 3' are mounted to turnabout a shaft within said casing with each of vanes 3 and 3' projectingfrom the shaft in the opposite direction. A hole is formed in the upperwall of the casing 1 above the position occupied by a cup-shaped vanewhen its open side is uppermost.

Each cup-shaped vane carries at one end an electromagnet 5. The poles ofthese two magnets facing the casing wall are of opposite polarities. Anelectromagnet 6 is mounted on the wall of the casing l in a positionsuch that, when it attracts a magnet 5, the cup carrying that magnetwill be in a position to receive a liquid dropped through said hole.

A reed switch 7, adapted to be closed when subjected to a magneticfield, is mounted on the side of the casing in a position such that itwill be thrown by the magnets 5 on the vanes as they swing past it. Thisswitch is connected to a counter 13 and a relay 8 for reversing thepolarity of the electromagnet 6.

A float 9 actuates a plug 4 which closes the hole through which the fuelis admitted when the level of fuel in the casing rises too high.Reference numeral 11 indicates the outlet from the casing and referencenumeral 12 an intermediate holding chamber.

In operation, liquid fuel supplied through the pipe C falls intowhichever of the two cup-shaped vanes 3,3 is waiting beneath the holethrough which said fuel is admitted. When a predetermined quantity offuel has fallen into the vane it swings downwardly, bringing its magnet5 past the reed switch 7, which temporarily closes thus transmitting apulse to the counter 13. This also temporarily closes a relay 8 whichreverses the polarity of the electromagnet 6, so that the end of themagnet 6 which formerly attracted the magnet S on the vane 3, now repelsthat vane, but attracts the magnet on the vane 3', and vice versa, thusbringing the next vane beneath the hole 4. The fuel then flows outthrough the outlet 11 into the holding chamber 12.

It will be appreciated that a larger number of cupshaped vanes may bemounted at equal radial distances about the shaft. Furthermore, simplermagnetic spotting means may then be used to spot the successive vanesbeneath the hole through which the fuel is admitted. For example, asimple permanent magnet may be carried by each vane, with the end of thesame polarity facing the casing wall in all cases. A simple permanentmagnet is likewise mounted in the casing wall with its pole of oppositepolarity adjacent the path of travel of the vane-mounted magnets. Whenthere are four or more vanes, the filling of one will depress it farenough to cause the magnet on the wall to attract the magnet on the nextvane.

What is claimed is:

1. A flow meter for measuring small quantities of liquids, which metercomprises:

means for supplying a downwardly directed stream of a liquid to bemeasured,

a plurality of cups mounted to rotate about a horizontal axis in a pathwhich brings said cups successively into a receiving position beneathsaid downwardly directed stream,

an electromagnet adjacent said receiving position,

and a magnet carried by each cup, each cupcarried magnet having a polelocated to be attracted by said electromagnet when near said receivingposition with a force insufficient to overcome the force exerted bygravity when only one of said cups is full of said liquid, and thosepoles of the magnets on adjacent cups which are positioned V to be thusattracted being of opposite polarity,

a reed switch positioned to be thrown by one of the magnets on said cupswhenever a cup departs from said receiving position,

means for reversing the polarity of said electromagnet in response tooperation of said reed switch, and

means actuated by said reed switch for indicating the volume of flow ofsaid liquid as a function of the number of departures of a cup from saidreceiving position.

1. A flow meter for measuring small quantities of liquids, which metercomprises: means for supplying a downwardly directed stream of a liquidto be measured, a plurality of cups mounted to rotate about a horizontalaxis in a path which brings said cups successively into a receivingposition beneath said downwardly directed stream, an electromagnetadjacent said receiving position, and a magnet carried by each cup, eachcup-carried magnet having a pole located to be attracted by saidelectromagnet when near said receiving position with a forceinsufficient to overcome the force exerted by gravity when only one ofsaid cups is full of said liquid, and those poles of the magnets onadjacent cups which are positioned to be thus attracted being ofopposite polarity, a reed switch positioned to be thrown by one of themagnets on said cups whenever a cup departs from said receivingposition, means for reversing the polarity of said electromagnet inresponse to operation of said reed switch, and means actuated by saidreed switch for indicating the volume of flow of said liquid as afunction of the number of departures of a cup from said receivingposition.